Electric switch



June 23, 1931. H; A SPAHR ELECTRIC ,SWITCH Filed Oct. l0, 1927 2Sheets-Sheet l June 23, 1931.

H. A. sPl-IR K 1,810,931

' y ELECTRIC SWITCH Filed 001'.. l0, 1927 2 Sheets-Sheet ,2

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Patented June 23, 1931 UNITED ASTATES AHOWARD A.. SIEAHR, OF MILWAUKEE,WISCONSIN ELECTRIC swrr'cn- Applicat'ion filed 0ctober'10, 1927. SerialNo. 225,221.

This invention relates to electric switches, and is particularlydirected to an electric switch of the push button type, Vpush pull type,or pendant switch type, or others of this general order.

` Objects of this invention are to provide a novel form of electricswitch which has a quick make and break, which is formed of a very smallnumber of parts, which may be made in any size or capacity, which 1sextremely compact, and in which the parts are very readily assembled. I

Further objects of this invention are to provide a switch which is soconstructed that the rocker bar may be positively dislodged by the pushbutton or manually operable member, for instance, in the event that therocker bar sticks and is not dislodged by the spring action, and toprovide a novel form of switch in which the rocker bar has a quickvmotion imparted thereto for either direction of travel of thereciprocatory member. Further objects are to provide an electric switchof the above type in which no mounting frame is required, but in whichthe parts rest upon the case and in which the stresses are borne by therocker arm and reciprocatory member and are not transmitted to the case.Y

Further objects are to provide a switch having a plunger and a rockerbar and a s spring in which the spring mounting is such that noadditional pins, thimbles, or other spring holding means are required,but inerates directly with the reciprocatory member to provide a pivotalmounting for the spring. Y

Further objects are to provide a 'switch in which a two part casing maybe employed to enclose the switch parts themselves in a novel mannerpermitting the stresses, as stated, to be borne by the rocker arm andplunger themselves instead of by the case,and without the ing in thescrews andthe switch `parts inthe event that one-half of the case isremoved stead the spring is so formed that it coop# use of any mountingframe, as stated above,A and to provide means for temporarily hold-vEmbodiments of the invention are shown in the accompanying drawings inwhich:

Figure l is a longitudinal sectional view on the line 1-1 of Figure 2;.A

Figure 2 is a'transverse sectional view on the line 2-2 of Figure 1;

Figure 3 is a transverse sectional view on the line 3-3 of Figures 1 and4;

Figure 4 is a plan view of a part ofthe casing with` the rocker bar andplunger removed;

Figure 5 is a side elevation of a modified form of switch with parts insection;v

Figure 6 is a longitudinall sectional view of a further form of switch.

Referring to the drawings, particularly Figures 1 to 4, it will be seenthat the switch comprises an upper .and a lower casing 1 and 2,respectively, which are held together by means of screws 3. These screwshave a reduced shank portion 4 which is smaller than l the threaded part5. i Further, it will be seen that the upper casing 1 is bored out, asindicated at 6, and has a threaded portion 7 whose internal diameter isslightly less 'than the bored out portion 6. This permits the insertionof the screw into the member 1 by screwing it through the threadedportion 7 Thereafter, the screw is held against coin-l plete dislodgmentfrom the member 1, although the member may be turned upside' down. Thevreason for this is that the enlarged threaded portion 5 merely contactswith the threaded portion 7 of the casing 1 and prevents the screws fromdroppingout.

This feature, although apparently only a de- A tail, is neverthelessextremely serviceable Jin connecting up the switch for it is notnecessary to carefully vremove the screws to prevent their loss as thescrews are automatically held to the upper casing.

Each of the casing members is provided with a out out portion S'whichtogether form a main compartment within which the rocker arm 9 ispositioned. This rocker arm is provided with a pair of trunnions 10ywhich may be formed by slipping rings over-the projecting ears 11 of.the rocker bar, as shown structions could he'used. These trunnions inFigure 3, although obviously other con- Y are received within slots orcutouts 12 formed in the lower casing member 2 and, if desired, a smallpiece of fibre or libre paper 13 may be slipped linto place above thetrunnions to prevent dislodgment of the rocker bar even if the switch isopened and the bottom casing inverted. 'This construction is shown mostclearly in Figures 1 and 2.`

It is to-be noted further that the upper. casing member 1 is providedwith a pair of downwardly extending lugs 14 which are positioned withinthe cutouts 12.

The lower casing member 2, as shown in Figure 4, is provided with twopair of stops l5 which are positioned on opposite sides of the centralcutout 8. These stops arrest the motion `or limit the extreme motionofthe rocking bar 9. Further, as shown in Figure 4, a pair ofstationarycontact ngers 16 may be. provided which, if desired, are madeof relatively springy brass or bronze, or other suitable material.Between these spring fingers the upper end of the rocking bar 9 isadapted to be positioned when the switch is closed. It is to be notedalso that the stops 15 are positioned inside of the contact 16 andconsequently in connecting up the switch, no

v displacement of the contacts can occureven though the operators screwdriver should strike one of the contacts. This is secured as statedbecause of the positioning of the stops 15 which act as limiting stopsfor the stationary contacts also.l In addition-to this, the stops 15 onthe side of the casing from the contacts provide guides for thethrough.wire andthus prevent the wire from becomingwlsntangled with themechanism.

e lower casing member 2 is provided with a pair of transverselypositioned'and aligned cutouts 17, similar cutout portions 18 beingprovided in the'upper "casin member. These cutout portions receive theinsulating handles 19 of the oscillatory or reciprocatory member whichoperates the rocking bar. The handles .are connected by means -of ametal body portion 2() and together with this metal body portion formthe oscillatory part of the switchf This metal body portionas downwardlyprojecting lugs 21 which are received within slots 22 formed in thelower casing mem-ber,`as shown most clearly in Figures 2 and 4c.

It is Ato be noted particularly'that the central portion of the rockerbar 9 is cut out and atits upper portion it is provided .with adownwardly extending lug 23 which receives the upper end of thecompression spring 24. The lower end of the compressionsprin'g has itslast convolution stopped half-way and has the last strand 25 bentdiametrically across the spring, as shown in Figure 2. This providesacentrally locatedbearing support for the spring which is formedintegrally with ceived. This reciprocatory member therefore i is heldagainst lateral rocking motion with respect to the rocking bar and alsoholds the rocking bar itself against lateral motion. Ing

addition to this, it may be found desirable to form the handles 19 (seeFigure 2) rectangular, and to correspondingly shape the notches orcutouts 17 and 18. l

The operation of the switch is as follows:

.Assume thatthe switch is open, as shown in Figure 2, and that theoperator presses the button or handle 19 inwardly. This causes thebottom pivot point of the spring to travel to the right in Figure 2, andin addition Ato this, one vof the projecting tongues 21 engages thedownwardly extending portion 9 of the rocking bar below the line ofthetrunnions. This starts thel rocking bar and the switch completes therocking motion in the left hand direction or counter clockwisedirection,as viewed in Figure 2. Thus, the switch has a quick make. `A reversemotion of the reciprocatory vmember will cause the other downwardlyprojecting member 21 to engage the lower end or portion 9 of the rockingbar, and a similar action will take place, the rocking bar thentravelling in a clockwise direction back into the position shown inFigure 2. This gives a quick break.

of the rocker bar, and in which the downwardly projecting lugs 21 of thereciprocatory member merely come into engagement withX the downwardlyprojecting portion of the rocker bar when the rocker bar tends to stick.

It is to be noted that the downwardly extending member 9 also acts as astop for the reciprocatory -member as it strikes against one or theother of the lugs 21 at the limit of motion ofthe switch. i l

It-nay be desirable to assemble the parts one from the bottom of theportion ofl the casing and the otherfrom the top. For instance, as shownin Figure 5, Ythe lower member 28 of the casing is similarly formed tothe member 2 of the casing, previously described, except that thetrunnion receiving notches or slots 29 open through its bottom edge andalso a slot is provided in the bottom .edge communicating with theseslots 29. The rocking bar 30 is substantiallysimilar to the rockingbarjpreviously described, except that it has a slot 31 through its upperside which extends downwardly between the projecting springreceivinglugs 32. This permits the positioning of t e reciprocatorymember 33.

The slot in the bottom portion of the casing 28 is closed in anysu1table manner as by followed as in Figure l, for instance, such memberbeing indicated by the reference character 35. Also, a similar type ofrocking bar 36 may be provided for engagingr the stationary contacts 37.Y The spring 38 1s mounted in the same way, as previously described.However, the casing members 39 are formed to provide an opening only atone end which receives the fitting 40. This fitting is threaded, asindicated at 41, and is adapted to be passed through a panel and securedby suitable nuts in a well-known manner. The

reciprocation member 35 has an extension 42 guided in one end of thecasing and at its other end is connected by means of an insulating strip43 with the operating handle or stem 44. The stem and insulating strip43 are guided in the fitting and consequently correctly support theouter end of the reciprocatory member 35. y

This form'of switch can be used as a push pull switch, if desired. Inaddition to this, it is clear that other forms of switches may beemployed which embody the invention disclosed in this case. Forinstance, the reciprocatory member could be urged in one direction by aspring so that it could be used as an instantaneous switch by merelypressing merely blanked out downwardly or inwardly upon the projectinghandle. Obviously, the casing could be changed so that the switch couldbe a pendant switch without departing from the spirit of this invention.Y

It is apparent that all of the forces due to the action of the springmay be borne internally, that is to say, may be borne by thereciprocatory member and the rocking bar and the forces of the springare not then transmitted to the supporting casing. In addition to this,it is also clear that no mounting frame need be used with this switch,thus very markedly simplifying its construction.

It is to be noted also that a novel form of switch has been provided inwhich no forming operations whatsoever are needed for the mechanismitself, that is to say, for the movable parts. Instead, these movableparts are of sheet material. Obviously, eliminating the formingoperations materially reduces thecost of the switch.

It has been found that the frictional loss and consequently the effortrequired to operate the switch is reduced to a minimum, although a stiffspring may be used. This, therefore, greatly increases the ease ofoperaaperture, said second tion of the switch.- Further, it is apparentfrom the description and the drawings that the switch has a very smallnumber of easily produced parts and that these parts may be assembledwith the utmost ease.

Although the invention has been described in considerable detail, suchdescription is intended as illustrative rather than limiting as theinvention may be variously embodied and as the scope of such inventionis to be determined as claimed.

I claim: y

1. An electric switch comprising a twopart casing, one of said partshaving a threaded aperture, screws carried by the other of said partsand extending into said threaded entioned part of the casing having a taded portion through which the threaded portion of the screw may bepassed, said screw having a shank of reduced diameter from the externaldiameter of the threadedpart, whereby the screw is prevented frominadvertently dropping from the `second mentioned portion. thereof, andswitch mechanism carried Within said casing.

2. -An electric switch comprising a pivoted rocking bar, stationarycontacts adapted to be engaged by said rocking bar, a reciprocatorymember for actuating said rocking bar, said rocking bar having adownwardly extending portion, lugs extending downwardly from saidreciprocatory member and adapted to engage said downwardly extendingportion of said rocking bar during the completion of the stroke of` thereciprocatory member in the event that said rocking bar sticks,

.said downwardly extending portion of said rocking bar also constitutinga stop for said lugs to limit the stroke of said reciprocatory member,and a compression spring between said rocking bar and said reciprocatorymember.

3. An electric switch comprising a base, a pivoted rocking bar carriedby said base, lstationary contacts adapted to be engaged by said rockingbar, a reciprocatory member for actuating said rocking bar, vacompression spring interposed between said reciprocatory member andsaidrocking bar, said spring holding said rocking bar and saidreciprocatory member to said base, said rocking bar having an openingand said reciprocatory member having a portion passing through saidopening, and means carried by-said reciprocatory member and adapted toengage said rocking-bar during the completion of ros the stroke of saidreciprocatory member in and said reciprocatory member, saidreciprocatory member having downwardly extending lugs and said rockingbar having a downwardly extending portion adapted to be engaged by saidlugs during the completion'of the stroke of the reciproeatory member inthe event of sticking of the rocking member, said rocking bar having asl with said opening, whereby said reciprocatory member may be passedthrough said slot during assembly.

In testimony that I claim the foregoing I have hereunto set my hand atMilwaukee, in the county of Milwaukee and State of Visconsin.

HOWARD A. SPAHR.

ot communicating

